I can't seem to log back in to stackoverflow.com now on my Mac (I'm still logged in on my PC). I'm getting the following error message (my OpenID provider is WordPress.com):

Unable to log in with your OpenID provider:

The following required parameters were missing from the DotNetOpenAuth.OpenId.Messages.CheckAuthenticationResponse message: is_valid

Update: I try logging out of WordPress.com, then logging back in to SO. WordPress.com asks me to sign in as usual, so I do it and refresh that page. And I get this:

Unable to log in with your OpenID provider:

Cannot decode Key-Value Form because a line was found without a ':' character. (line 3: '<head>')

I reload SO's login page and try logging in with my WordPress.com OpenID again. However many times I try that now, I no longer get the first error, only the second.

From the looks of the errors, they seem to be the ones slipping up. Should I report this issue to them too, just in case? I've contacted them with a link to this question.

Just to add: I don't get automatically signed in to the main site even though I'm still logged into meta on my Mac, as well as a bunch of other Stack Exchange sites. I don't know if this has anything to do with the WordPress.com issue though.

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3

that is odd, I would definitely open a support ticket on their end. We haven't changed anything in a long, long time.
–
Jeff Atwood♦Jan 28 '11 at 12:13

2

@Jeff: yeah I just shot them a support mail at the same time you left the comment. I definitely think it's their fault more than ours.
–
BoltClock's a UnicornJan 28 '11 at 12:14

Strange; I first noticed a problem Thursday night, and it was the same on Friday but with new error messages. I searched for questions both times (with the specific errors) but couldn't see anything relevant, so I posted my own. Perhaps this question was not high enough on the list of results at that time. Can you add a WordPress tag to this question?
–
Mark CJan 29 '11 at 16:21

People, you can go to your profile, click in the "accounts" tab and click the link "add openid" in front of the "Registered User" title - and add a new OpenID. That is what I did to be able to comment here. Also, you all probably have more than one OpenID (or you do not have a Gmail account or Facebook profile? :) )
–
brandizziJan 31 '11 at 16:42

Definitely looks like a problem on the WordPress end. I repro the problem at http://test-id.org/OP/Sreg.aspx when entering my WordPress OpenID and get the same error. Their OP Endpoint is broken. The logs from test-id.org show they aren't handling OpenID associations nor are they responding correctly to the check_auth verification step.